Defender 90 R380 box

[yellow90]

hello there.

got prob with my 90, 300 tdi with 380 box fitted.

transfer box failed, whinning due to lack of oil and have removed to reveal very little splines on output shaft. is a disco 300 gearbox the same and are there any mods needed if i fit one, complete with transfer box? (only cause they're cheaper)

i know this will gear it up, which i am not fussed about as i use it mainly on roads without towing etc.

thanks for help.

[zim]

hello there.

got prob with my 90, 300 tdi with 380 box fitted.

transfer box failed, whinning due to lack of oil and have removed to reveal very little splines on output shaft. is a disco 300 gearbox the same and are there any mods needed if i fit one, complete with transfer box? (only cause they're cheaper)

i know this will gear it up, which i am not fussed about as i use it mainly on roads without towing etc.

thanks for help.

sorry, it won't fit. the box is longer in the disco.

Gordon

[ciderman]

I thought the only difference was were the two gearstck positions were reversed .

If its a good box otherwise , why not have a new shaft fitted into it .

[ThreeSheds]

I am thinking that if you only need the transfer box and don't mind the gearing-up issue, then that would fit on the back of your existing gearbox wouldn't it?

[vinny]

Ive just rebuilt a disco r380 as a defender r380. The selector shaft and the selector fork/linkage need to be changed. You will have these from your own box anyway.

[FridgeFreezer]

Are you talking about putting a Disco R380 into a Defender or putting a Disco LT230 on the back of a Defender R380 here?

The Disco box will be longer in the bellhousing/input shaft and the gearchange mech & tail casting are different, it's possible to swap everything over but it's a fair bit of hassle. The Disco R380 will not change your gearing by any noticeable amount. I'm not sure why you say Disco ones are cheaper, Ashcroft seem to charge the same money for a recon unit whatever it is.

If you mean the LT230 then, yes it will fit and yes it will raise your gearing.

Whatever you do, I'd fit a cross-drilled input gear to provide lubrication to the splines in the future.

LT 230 Transfer case comparisons

1.003 > 1.222 = 17.92% Drop mph/1000

1.003 > 1.410 = 28.86% Drop

1.003 > 1.667 = 39.83% Drop

1.222 > 1.003 = 21.80% Raise

1.222 > 1.410 = 13.33% Drop

1.222 > 1.667 = 26.70% Drop

1.410 > 1.003 = 40.57% Raise

1.410 > 1.222 = 15.38% Raise

1.410 > 1.667 = 15.41% Drop

1.667 > 1.003 = 66.20% Raise

1.667 > 1.222 = 36.41% Raise

1.667 > 1.410 = 18.22% Raise

For those considering a ratio change the following may prove useful. MPH per 1000 rpm = 2.976D/ MTR

D Tyre diameter in inches (more accurate to use 2 x rolling radius)

M Typical 5 speed manual box, select a ratio 1st 3.60 These ratios will vary a little between box types 2nd 2.11 3rd 1.40 4th 1.00 5th 0.77 Rev 3.43

T Transfer ratio select a ratio

High 1.003 1.222 1.410 1.667 Low 3.321

R Differential select a ratio 4.70 S 4.11 L 3.54 S L Special

S stock

[vinny]

The Disco box will be longer in the bellhousing/input shaft and the gearchange mech & tail casting are different, it's possible to swap everything over but it's a fair bit of hassle. splines in the future.

Forgot about the case and to change the input shaft you need a set of bearing pullers to strip part of the output shaft.